PDS_VERSION_ID                = PDS3                                          
RECORD_TYPE                   = STREAM                                        
LABEL_REVISION_NOTE           = "                                             
2016-06-15 SwRI:BTCarcich                                                     
  New file                                                                    
"                                                                             
                                                                              
OBJECT                        = TEXT                                          
  PUBLICATION_DATE            = 2016-06-15                                    
  NOTE                        = "The NH LORRI pluto cruise                    
                                 Calibrated VERSION 2.0                       
                                 Data Archive                                 
                                                                              
                                 Directory naming conventions                 
                                                                              
                                "                                             
END_OBJECT                    = TEXT                                          
END                                                                           
                                                                              
                                                                              
Data directory naming convention                                              
================================                                              
                                                                              
All of the data files in this dataset are under, but not in, the top-level    
/DATA/ directory.  Sub-directories, based on the MET (see above) of the       
top-level /DATA/ directory have been provided to increase the granularity of  
data storage locations which in turn keeps there from being too many data     
files in any one directory.  The granularity implemented is one sub-directory 
per 10,000 counts of the MET (see Data Filenames and Product IDs section      
above).                                                                       
                                                                              
The subdirectory names on this volume reflect that granularity.  These        
names are of the form                                                         
                                                                              
  YYYYMMDD_MET/                                                               
                                                                              
where MET is a grouping of the first six digits of the ten-digit MET          
count, and YYYY, MM, and DD are the year, month and day of the first          
possible MET corresponding to that six-digit MET prefix.  Any data file       
will be located in a directory whose six-digit MET prefix matches that        
of the data file.                                                             
                                                                              
Since each count represents about one second, there may be as many as nine    
six-digit MET prefixes with the same YYYYMMDD values.  Also, since days       
will not start or end exactly on 10,000 count MET boundaries, directories     
with the naming convention may span day boundaries.  That is, the YYYYMMDD    
value corresponding to the start of a 10,000 count MET range may not be       
the same as the YYYYMMDD that corresponds to the end of that range.           
                                                                              
                                                                              
Explanation of granularity                                                    
--------------------------                                                    
                                                                              
The granularity of sub-directories under /DATA/ on this volume has been       
copied from that used on the Science Operations Center (SOC) where the        
data files were originally generated.  On the SOC, the same granularity       
was implemented across all eight New Horizons instruments' directory          
structures.  Because the mission instruments generate data files at           
varying rates, from one or more data files per second to one or more days     
per data file, a compromise granularity of 10,000 MET counts was chosen,      
and propagated to this volume.